package org.bouncycastle.jce.provider;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.math.BigInteger;
import java.security.interfaces.ECPublicKey;
import java.security.spec.ECParameterSpec;
import java.security.spec.ECPoint;
import java.security.spec.ECPublicKeySpec;
import java.security.spec.EllipticCurve;

import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1Object;
import org.bouncycastle.asn1.ASN1OctetString;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.DERBitString;
import org.bouncycastle.asn1.DERNull;
import org.bouncycastle.asn1.DERObject;
import org.bouncycastle.asn1.DERObjectIdentifier;
import org.bouncycastle.asn1.DEROctetString;
import org.bouncycastle.asn1.x509.AlgorithmIdentifier;
import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
import org.bouncycastle.asn1.x9.X962Parameters;
import org.bouncycastle.asn1.x9.X9ECParameters;
import org.bouncycastle.asn1.x9.X9ECPoint;
import org.bouncycastle.asn1.x9.X9IntegerConverter;
import org.bouncycastle.asn1.x9.X9ObjectIdentifiers;
import org.bouncycastle.crypto.params.ECDomainParameters;
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
import org.bouncycastle.jce.interfaces.ECPointEncoder;
import org.bouncycastle.jce.provider.asymmetric.ec.EC5Util;
import org.bouncycastle.jce.provider.asymmetric.ec.ECUtil;
import org.bouncycastle.jce.spec.ECNamedCurveSpec;
import org.bouncycastle.math.ec.ECCurve;

public class JCEECPublicKey implements ECPublicKey,
        org.bouncycastle.jce.interfaces.ECPublicKey, ECPointEncoder {
    private static final long serialVersionUID = 7802147799709084976L;
    private String algorithm = "EC";
    private org.bouncycastle.math.ec.ECPoint q;
    private ECParameterSpec ecSpec;
    private boolean withCompression;

    // BEGIN android-removed
    // private GOST3410PublicKeyAlgParameters gostParams;
    // END android-removed

    public JCEECPublicKey(String algorithm, JCEECPublicKey key) {
        this.algorithm = algorithm;
        this.q = key.q;
        this.ecSpec = key.ecSpec;
        this.withCompression = key.withCompression;
        // BEGIN android-removed
        // this.gostParams = key.gostParams;
        // END android-removed
    }

    public JCEECPublicKey(String algorithm, ECPublicKeySpec spec) {
        this.algorithm = algorithm;
        this.ecSpec = spec.getParams();
        this.q = EC5Util.convertPoint(ecSpec, spec.getW(), false);
    }

    public JCEECPublicKey(String algorithm,
            org.bouncycastle.jce.spec.ECPublicKeySpec spec) {
        this.algorithm = algorithm;
        this.q = spec.getQ();

        if (spec.getParams() != null) // can be null if implictlyCa
        {
            ECCurve curve = spec.getParams().getCurve();
            EllipticCurve ellipticCurve = EC5Util.convertCurve(curve, spec
                    .getParams().getSeed());

            this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
        } else {
            if (q.getCurve() == null) {
                org.bouncycastle.jce.spec.ECParameterSpec s = ProviderUtil
                        .getEcImplicitlyCa();

                q = s.getCurve().createPoint(q.getX().toBigInteger(),
                        q.getY().toBigInteger(), false);
            }
            this.ecSpec = null;
        }
    }

    public JCEECPublicKey(String algorithm, ECPublicKeyParameters params,
            ECParameterSpec spec) {
        ECDomainParameters dp = params.getParameters();

        this.algorithm = algorithm;
        this.q = params.getQ();

        if (spec == null) {
            EllipticCurve ellipticCurve = EC5Util.convertCurve(dp.getCurve(),
                    dp.getSeed());

            this.ecSpec = createSpec(ellipticCurve, dp);
        } else {
            this.ecSpec = spec;
        }
    }

    public JCEECPublicKey(String algorithm, ECPublicKeyParameters params,
            org.bouncycastle.jce.spec.ECParameterSpec spec) {
        ECDomainParameters dp = params.getParameters();

        this.algorithm = algorithm;
        this.q = params.getQ();

        if (spec == null) {
            EllipticCurve ellipticCurve = EC5Util.convertCurve(dp.getCurve(),
                    dp.getSeed());

            this.ecSpec = createSpec(ellipticCurve, dp);
        } else {
            EllipticCurve ellipticCurve = EC5Util.convertCurve(spec.getCurve(),
                    spec.getSeed());

            this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec);
        }
    }

    /*
     * called for implicitCA
     */
    public JCEECPublicKey(String algorithm, ECPublicKeyParameters params) {
        this.algorithm = algorithm;
        this.q = params.getQ();
        this.ecSpec = null;
    }

    private ECParameterSpec createSpec(EllipticCurve ellipticCurve,
            ECDomainParameters dp) {
        return new ECParameterSpec(ellipticCurve, new ECPoint(dp.getG().getX()
                .toBigInteger(), dp.getG().getY().toBigInteger()), dp.getN(),
                dp.getH().intValue());
    }

    public JCEECPublicKey(ECPublicKey key) {
        this.algorithm = key.getAlgorithm();
        this.ecSpec = key.getParams();
        this.q = EC5Util.convertPoint(this.ecSpec, key.getW(), false);
    }

    JCEECPublicKey(SubjectPublicKeyInfo info) {
        populateFromPubKeyInfo(info);
    }

    private void populateFromPubKeyInfo(SubjectPublicKeyInfo info) {
        // BEGIN android-removed
        // if
        // (info.getAlgorithmId().getObjectId().equals(CryptoProObjectIdentifiers.gostR3410_2001))
        // {
        // DERBitString bits = info.getPublicKeyData();
        // ASN1OctetString key;
        // this.algorithm = "ECGOST3410";
        //
        // try
        // {
        // key = (ASN1OctetString) ASN1Object.fromByteArray(bits.getBytes());
        // }
        // catch (IOException ex)
        // {
        // throw new IllegalArgumentException("error recovering public key");
        // }
        //
        // byte[] keyEnc = key.getOctets();
        // byte[] x = new byte[32];
        // byte[] y = new byte[32];
        //
        // for (int i = 0; i != x.length; i++)
        // {
        // x[i] = keyEnc[32 - 1 - i];
        // }
        //
        // for (int i = 0; i != y.length; i++)
        // {
        // y[i] = keyEnc[64 - 1 - i];
        // }
        //
        // gostParams = new
        // GOST3410PublicKeyAlgParameters((ASN1Sequence)info.getAlgorithmId().getParameters());
        //
        // ECNamedCurveParameterSpec spec =
        // ECGOST3410NamedCurveTable.getParameterSpec(ECGOST3410NamedCurves.getName(gostParams.getPublicKeyParamSet()));
        //
        // ECCurve curve = spec.getCurve();
        // EllipticCurve ellipticCurve = EC5Util.convertCurve(curve,
        // spec.getSeed());
        //
        // this.q = curve.createPoint(new BigInteger(1, x), new BigInteger(1,
        // y), false);
        //
        // ecSpec = new ECNamedCurveSpec(
        // ECGOST3410NamedCurves.getName(gostParams.getPublicKeyParamSet()),
        // ellipticCurve,
        // new ECPoint(
        // spec.getG().getX().toBigInteger(),
        // spec.getG().getY().toBigInteger()),
        // spec.getN(), spec.getH());
        //
        // }
        // else
        // END android-removed
        {
            X962Parameters params = new X962Parameters((DERObject) info
                    .getAlgorithmId().getParameters());
            ECCurve curve;
            EllipticCurve ellipticCurve;

            if (params.isNamedCurve()) {
                DERObjectIdentifier oid = (DERObjectIdentifier) params
                        .getParameters();
                X9ECParameters ecP = ECUtil.getNamedCurveByOid(oid);

                curve = ecP.getCurve();
                ellipticCurve = EC5Util.convertCurve(curve, ecP.getSeed());

                ecSpec = new ECNamedCurveSpec(ECUtil.getCurveName(oid),
                        ellipticCurve, new ECPoint(ecP.getG().getX()
                                .toBigInteger(), ecP.getG().getY()
                                .toBigInteger()), ecP.getN(), ecP.getH());
            } else if (params.isImplicitlyCA()) {
                ecSpec = null;
                curve = ProviderUtil.getEcImplicitlyCa().getCurve();
            } else {
                X9ECParameters ecP = new X9ECParameters(
                        (ASN1Sequence) params.getParameters());

                curve = ecP.getCurve();
                ellipticCurve = EC5Util.convertCurve(curve, ecP.getSeed());

                this.ecSpec = new ECParameterSpec(ellipticCurve, new ECPoint(
                        ecP.getG().getX().toBigInteger(), ecP.getG().getY()
                                .toBigInteger()), ecP.getN(), ecP.getH()
                        .intValue());
            }

            DERBitString bits = info.getPublicKeyData();
            byte[] data = bits.getBytes();
            ASN1OctetString key = new DEROctetString(data);

            //
            // extra octet string - one of our old certs...
            //
            if (data[0] == 0x04 && data[1] == data.length - 2
                    && (data[2] == 0x02 || data[2] == 0x03)) {
                int qLength = new X9IntegerConverter().getByteLength(curve);

                if (qLength >= data.length - 3) {
                    try {
                        key = (ASN1OctetString) ASN1Object.fromByteArray(data);
                    } catch (IOException ex) {
                        throw new IllegalArgumentException(
                                "error recovering public key");
                    }
                }
            }
            X9ECPoint derQ = new X9ECPoint(curve, key);

            this.q = derQ.getPoint();
        }
    }

    public String getAlgorithm() {
        return algorithm;
    }

    public String getFormat() {
        return "X.509";
    }

    public byte[] getEncoded() {
        ASN1Encodable params;
        SubjectPublicKeyInfo info;

        // BEGIN android-removed
        // if (algorithm.equals("ECGOST3410"))
        // {
        // if (gostParams != null)
        // {
        // params = gostParams;
        // }
        // else
        // {
        // if (ecSpec instanceof ECNamedCurveSpec)
        // {
        // params = new GOST3410PublicKeyAlgParameters(
        // ECGOST3410NamedCurves.getOID(((ECNamedCurveSpec)ecSpec).getName()),
        // CryptoProObjectIdentifiers.gostR3411_94_CryptoProParamSet);
        // }
        // else
        // { // strictly speaking this may not be applicable...
        // ECCurve curve = EC5Util.convertCurve(ecSpec.getCurve());
        //
        // X9ECParameters ecP = new X9ECParameters(
        // curve,
        // EC5Util.convertPoint(curve, ecSpec.getGenerator(), withCompression),
        // ecSpec.getOrder(),
        // BigInteger.valueOf(ecSpec.getCofactor()),
        // ecSpec.getCurve().getSeed());
        //
        // params = new X962Parameters(ecP);
        // }
        // }
        //
        // BigInteger bX = this.q.getX().toBigInteger();
        // BigInteger bY = this.q.getY().toBigInteger();
        // byte[] encKey = new byte[64];
        //
        // extractBytes(encKey, 0, bX);
        // extractBytes(encKey, 32, bY);
        //
        // info = new SubjectPublicKeyInfo(new
        // AlgorithmIdentifier(CryptoProObjectIdentifiers.gostR3410_2001,
        // params.getDERObject()), new DEROctetString(encKey));
        // }
        // else
        // END android-removed
        {
            if (ecSpec instanceof ECNamedCurveSpec) {
                DERObjectIdentifier curveOid = ECUtil
                        .getNamedCurveOid(((ECNamedCurveSpec) ecSpec).getName());
                if (curveOid == null) {
                    curveOid = new DERObjectIdentifier(
                            ((ECNamedCurveSpec) ecSpec).getName());
                }
                params = new X962Parameters(curveOid);
            } else if (ecSpec == null) {
                params = new X962Parameters(DERNull.INSTANCE);
            } else {
                ECCurve curve = EC5Util.convertCurve(ecSpec.getCurve());

                X9ECParameters ecP = new X9ECParameters(curve,
                        EC5Util.convertPoint(curve, ecSpec.getGenerator(),
                                withCompression), ecSpec.getOrder(),
                        BigInteger.valueOf(ecSpec.getCofactor()), ecSpec
                                .getCurve().getSeed());

                params = new X962Parameters(ecP);
            }

            ECCurve curve = this.engineGetQ().getCurve();
            ASN1OctetString p = (ASN1OctetString) new X9ECPoint(
                    curve.createPoint(this.getQ().getX().toBigInteger(), this
                            .getQ().getY().toBigInteger(), withCompression))
                    .getDERObject();

            info = new SubjectPublicKeyInfo(new AlgorithmIdentifier(
                    X9ObjectIdentifiers.id_ecPublicKey, params.getDERObject()),
                    p.getOctets());
        }

        return info.getDEREncoded();
    }

    @SuppressWarnings("unused")
    private void extractBytes(byte[] encKey, int offSet, BigInteger bI) {
        byte[] val = bI.toByteArray();
        if (val.length < 32) {
            byte[] tmp = new byte[32];
            System.arraycopy(val, 0, tmp, tmp.length - val.length, val.length);
            val = tmp;
        }

        for (int i = 0; i != 32; i++) {
            encKey[offSet + i] = val[val.length - 1 - i];
        }
    }

    public ECParameterSpec getParams() {
        return ecSpec;
    }

    public org.bouncycastle.jce.spec.ECParameterSpec getParameters() {
        if (ecSpec == null) // implictlyCA
        {
            return null;
        }

        return EC5Util.convertSpec(ecSpec, withCompression);
    }

    public ECPoint getW() {
        return new ECPoint(q.getX().toBigInteger(), q.getY().toBigInteger());
    }

    public org.bouncycastle.math.ec.ECPoint getQ() {
        if (ecSpec == null) {
            if (q instanceof org.bouncycastle.math.ec.ECPoint.Fp) {
                return new org.bouncycastle.math.ec.ECPoint.Fp(null, q.getX(),
                        q.getY());
            } else {
                return new org.bouncycastle.math.ec.ECPoint.F2m(null, q.getX(),
                        q.getY());
            }
        }

        return q;
    }

    public org.bouncycastle.math.ec.ECPoint engineGetQ() {
        return q;
    }

    org.bouncycastle.jce.spec.ECParameterSpec engineGetSpec() {
        if (ecSpec != null) {
            return EC5Util.convertSpec(ecSpec, withCompression);
        }

        return ProviderUtil.getEcImplicitlyCa();
    }

    public String toString() {
        StringBuffer buf = new StringBuffer();
        String nl = System.getProperty("line.separator");

        buf.append("EC Public Key").append(nl);
        buf.append("            X: ")
                .append(this.q.getX().toBigInteger().toString(16)).append(nl);
        buf.append("            Y: ")
                .append(this.q.getY().toBigInteger().toString(16)).append(nl);

        return buf.toString();

    }

    public void setPointFormat(String style) {
        withCompression = !("UNCOMPRESSED".equalsIgnoreCase(style));
    }

    public boolean equals(Object o) {
        if (!(o instanceof JCEECPublicKey)) {
            return false;
        }

        JCEECPublicKey other = (JCEECPublicKey) o;

        return engineGetQ().equals(other.engineGetQ())
                && (engineGetSpec().equals(other.engineGetSpec()));
    }

    public int hashCode() {
        return engineGetQ().hashCode() ^ engineGetSpec().hashCode();
    }

    private void readObject(ObjectInputStream in) throws IOException,
            ClassNotFoundException {
        byte[] enc = (byte[]) in.readObject();

        populateFromPubKeyInfo(SubjectPublicKeyInfo.getInstance(ASN1Object
                .fromByteArray(enc)));

        this.algorithm = (String) in.readObject();
        this.withCompression = in.readBoolean();
    }

    private void writeObject(ObjectOutputStream out) throws IOException {
        out.writeObject(this.getEncoded());
        out.writeObject(algorithm);
        out.writeBoolean(withCompression);
    }
}
